Automatic drill head



Jan 19, 1932. w. K. MILLHOLLAND 1,841,546

AUTOMATIC DRILL HEAD INVENTOR.' II//zL/HM A, /V/u/faun/va,

BY E W A RNEYJ,

Jan. 19, 1932.

W.VK. MILLHOLLAND AUTOMATIC DRILL HEAD Filed March 2, 1927 2 Sheets-Sheet 2 WM Y Pateaied Jan. 19, 1932 UNITED STATES WILLIAM MIILHOLLAND, F INDIANAPOLIS,

AUTOMATIC DRILL BEAD Application mea men 2, 1927.' serial no. 172,148.

range the same so thatit will have a quick advance to the work, proper feed while working and quick return when the' work has been completed, and which has the further advantage that it will only feed to a 'certain I depth on the work.

The several objects hereinbefore mentioned are attained by certain structural arrangements hereinafter morespecifcally pointed out.

The full nature of the invention will be understood from the accompanying draw.

ings vand the following description and claims:

. In the drawings Fig. l is in general a lon- 2,5 gitudinal sectional view throughl the machine. Fig. 2 is va transverse sectional view lthrough the machine and is taken substantially in the plane of 2-2 of Fig. l and inthe direction of the arrows. Fig. 3 is a trans' verse sectional view taken substantially 1n h the plane 3-3 of Fig. 1 and in the direction of the arrows. Fig. 4 is a transverse sectional view taken substantially in the plane of 4 4 of Fig. 1 andin the direction of the arrows. Fig. 5 is a sectional view showing in plan the cam and rod connection.

In the drawings there is illustrated the several structural arrangements comprising the machine, and it is to be noted that all of said parts are not shown in any one predetermined position, but certain of the parts are shown in positions other than a specific' position corresponding to other specific positionsl of other parts of the machine in order to more clearly illustrate the relationship of the first mentioned parts. Since abrief and also a detailed description of the operation of the machine will beincluded hereinafter, 5 no possibility of error will result by reason of the drawings illustrating the lparts as shown.

Briefly, the machine consists of a spindle for drilling and the like which is directly rotated from the powersupply which may be a direct drive such as an electric motor mounted on the end thereof, or mounted ad-Y jacent thereto and driven through the usual standard gear reduction, or as herein shown, the spindle is rotated by a pulley in turn suitably driven. Thus, the spindle is positively driven and at a relatively high and the desired rate of speed. The spindle is sipported by a longitudinal feeding sleeve slidably mounted for advancing the spindleV to and from the work and the connection and controls between the drive or power and the sleeve constitutes one of the chief features of the invention. Through a speed reduction arrangement, vherein worm, and worm wheel and gearv and pinion, a suitably fashioned cam positively rotated and actuates a cam engaging follower connected to the spindle supporting sleeve for vreciprocating the spindle as aforesaid. Interposed in the speed re,- duction set forth, is a clutch construction.

- which is manually actuated to initiate feeding movement of the spindle toward the work, i. and said clutch construction is so arranged that it is controlled by other mechanism autoinatically operable by the'longitudinal spindle movement upon return of the spindle to. the initial position to discontinue. any further longitudinal movement of said spindle. This will permit the operator to replace'the 85 work and again manually initiate the cycle of operation. The cam makes one complete revolution per cycle of operation.

` In the drawings, l0 indicates a suitable substantially hollow frame for the unit which is p rovided at the bottom with inclined pro# )ecting portions or the like for mounting upon vthe ways of a lathe'bed or'the like. The top part o f the base a't 12 is provided with suitable aligning slots and the like to .permit the mounting of suitable guides or other mech-` anism that might be utilized to assist in the accomplishment of o the formation of the work.y This may be by way of securing additional tool or work alignment. Extending the driving spindle.

"splined relation with another sleeve 20, the

spline being indicated at 21 and the sleeve 2O has an elongated splined relationship with the longitudinal opening or groove 13 by the spline 22. Sleeve 20 thus is permitted to reciprocate longitudinally of the spindle axis but 'cannot rotate. Similarly sleeve 18 can be reciprocated 'longitudinally of sleeve 20 but cannot rotate relative thereto. Thus, by reason of the construction of the head on sleeve 18 reciprocation of the sleeve will cause reciprocation of the spindle towards and away from the work. The means for adjusting the mechanism to secure positive depth of cut will be set forth hereinafter.

The spindle 14 beyond the bearing 17 is reduced as at 24 and is further reduced as at 25 land is keyed as at 27 to a sleeve 28. This has its forward end rotatably mounted in the ant-imined axial position at all times.

.friction bearing 29 and another portion mounted is the anti-friction bearing 30, these thereby supporting 'the shaft in precIleterntermediate said bearing said sleeve has its exterior provided with worm teeth 31 which mesh wlth a worm wheel 32 mounted on shaft 33 transversely positioned in and supported by frame 10. The sleeve 28 is extended beyond the anti-friction bearing 30 and is keyed as at 34 to a sleeve 35 in turn keyed at 36 to a driving pulley 37. As previously set forth other motive power means may be substituted therefor. The race retainer 38 and pulley retainer 39 complete the driving connection and mounting. Thus, the spindle 14 is directly connected for rotation, but is permitted to have lon itudinal movement relative to its support w ile rotating by reason of the elongated key connections 27.

The shaft 33 is keyed to a pinion 40, see Fig. 2, which meshes with a gear 41, see Figs. 2 and 3, carried by a shaft 42. Interposed between the shaft 33 and worm wheel 32 is a clutch construction shown particularly in Fig. 2. The clutch construction includes a sleeve 43 rotatably mounted on shaft 33 and splined to the worm wheel at 143, and also having an elongated spine connection, 144, with a shiftillustrated. A yoke 47 is carried by a rod 48 and the first mentioned is adjustably mounted on said rod at 148. A spring 49 coaxial with the rod normally tends to position the clutch collar 44 in the clutch disengaging position. Rod 48 projects outwardly and terminates in a cam face 50 adapted to engage a complevmentary portion formed on a plunger 51.

When plunger 51 is actuated to position the `rod 48, as shown in Fig. 2, the clutch is engaged and direct driving connection is obtained. When the plunger 51 is retracted rod 48 is projected to the right by spring 49 and the clutch is disengaged. The same means which causes movement of plunger 51 to se'- cure clutch engagement may secure clutch disengagement. However, means is provided for automatically shifting said plunger 51 to secure clutch'disengagement of said means and the same will be described in detail hereinafter. Through this provision single cycle operation is obtained.

Shaft 42, see Fig. 3, has keyed thereon a bushing or sleeve 52 and supported by said sleeve or bushing is a cam 53 and said cam is clampingly mounted on said bushing by the nut 154. Thus, the position of the cam can be adjusted by the aforesaid clamping construction relative to the position of the shaft 42. Cam 53 is adapted to engage a roller 54, see Fig. 4, carried by pin or stub shaft 55. Stub shaft 55 is carried by a lever 56 mounted on the pin 57 and is suitably secured thereto as by the set screw 58, and said pin is pivotally supported at 59 in the framework, see Fig. 4. A spring 60, through suitable means 61 and 62 upon the lever 56 and frame 10, serves to position said spring such that it will normally tend to cause the roller 54 to engage the cam 53. 4The upper end of the lever 56,see Fig. 1, is bifurcated to receive a link 63 also pivotally mounted on the stub shaft 55. Link 63 is pivotally mounted at 64 in the ears 65 carried bv the reciprocating sleeve 20. Through sleeve 20 sleeve 18 together with the spindle 24 will be reciprocated positively by the tilting of the lever 56 by reason of said cam and roller engagement. The cam 53 is of such character that preferably it will cause the sleeve 20 to quickly advance to the Work. then feed the tool to the Work at the proper speed and to the adjusted depth and then permit the quick return of the spindle by reason of the spring 60.

Adjustably mounted on the rod '51 by means of set screw 66 is a bracket 67 and yieldingly mounted therein is a plunger 68 backed by spring 168. Suitablv supported upon the cam and rotatable therewith is a tripping device 69 and the same is so positioned relative to plunger 68 that when the spindle and sleeves 14` 18 and 20, respectively, have been returned to the retracted osition to permit removal of the work fo owing operation thereon, the cam 67 depresses `lever pivoted at 71 from the fra-me is tripped or an equivalent mechanism is actuated to move plunger 51' toward the right and thus cause clutch 4engagement and initiate the cycle of operation. Upon the completion of the cycle of operationipower is disconnected as aforesaid, and further feeding or longitudinal movement ceases.

The several parts of the mechanism are protected by the plates-73, 74, and 75.

From the fore oing it will be understood that positive feeingmovement is obtained and for any given cam and pulley speed the.

feeding movement will be constant. It is required to adjust the position of the tool to secure operation to a predetermined positive depth, it being understood that the frame 10 is clamped or mounted in substantially the desired position to -secure such positive depth engagement or working by the tool employed. However, to positively insure accuracy, the sleeves 18 and 20 may be longitudinally shifted relatively of each other and secured in such adjusted position. Herein the exterior of sleeve 18 is shown provided with a thread 80 and rigidly mounted upon the face of the sleeve 20 is a clamping ring 81 which encircles a threaded nut 82. Flg. 1 shows the aforesaid in the completely retracted position. To secure positive de th adjustment the threaded nut 82 is rotate and since sleeves 18 and 20 l cannot rotate relatively of each other, sleeve 18 is caused to slide relative to sleeve 20 by reason of rotation of nut 82. When the spindle is secured in the predetermined position to secure positive depth operation of the tool, the locking member 83 carried by the locking ring 8l4 engages the internally threaded nut 82 and, clamps the same upon the sleeve 18 in the adjusted position. Sleeves 18 and 20 lthereafter move as a unit under the friction cam and spring 60.

The invention claimed is: j

1. A power tool unit including a base having a boreextending longitudinally therethrough, a multipart telescopic spindle mounted therein including a tool supporting exposed end and a driving end, a reciprocable member adjacent the tool supporting end of the spindle for reciprocating the same, a source of rotational power connected to'the opposite lend of said spindle for constantly ,in and splined to one sleeve an ciated with the sleeve for rotation thereby a clutch driven by said means, means inde-4 pendently initiable for clutch disengagement including a reciprocable rod having a cam portion, aclutch shifter, a spring normall constraining said shifter toward clutch disengagement, a member movable withthe shifter and having a co-operating portion operatively associated with the rod cam portion, a yielding latch and catch construction one portion of which is rotatable, and the other portion of which is carried by said rod, the latter being movable by the rotatable portion for shifting the rod opposite to its initial l movement to cause clutch. disengagement upon completion of the cycle, and a fiat member with a cam periphery and havin cyclic movement,-rotatable by the clutch w en engaged for moving the member for positive spindle feeding and for rotating the latchy and catch rotatable portion.

2. 'A power tool unit including a bod portion having a bore extending longitudinally therethrough near the upper portion thereof, a pair of axially aligned sleeves in said bore, a tool supporting spindle slidabl mounted rotatably mounted in. the other sleeve andconnected thereto for reciprocation therewith ashaft transverse of the spindle beneath the same, a fiat cam on said shaft and with a cam pberiphery, an oscillatory member operable y the cam and operatively connected to the reciprocatory sleeve for spindle reciprocation, spring means normally constraining the mem- Y ber into one position, the cam effecting movement in the opposite direction for positive forward feeding of the spindle, a sourcen of rotational power for driving the rotating sleeve, a worm and worm wheel type driving connection between the rotatin sleeve an the shaft, a clutch interposed etween the driving connection and the oscillatory member, and manually operable means for moving a stopping mechanism into operativeposition for engagement by a cooperating rotating member upon cycle completion for automatic stopping ofthe spindle reciprocation when the spindle is retracted, said manually operable means simultaneously causing clutch engagement, clutch disengagement occurring when the stopping mechanism is engaged.

In witness whereof, I have hereunto affixed my signature. v

WILLIAM K. MILLHOLLAND. 

